The development and implementation of the mass spectrometry core is essential to the research of the listed[unreadable] principal investigators. In particular the core will provide mass spectral analysis using the proposed bottomup[unreadable] and top-down methods employing both Q-TOF technology as well as FTICR high-resolution analysis.[unreadable] Both a top-down (intact protein identification) and a bottom-up (protein digestion) approach will be used to[unreadable] identify proteins of the various ribosomal complexes. Differences in post-translational modifications will be[unreadable] determined for ribosome complexes which have been subjected to infection by various viruses (hepatitis c,[unreadable] dengue, etc). eif3 factors associated with the ribosome will be analyzed and investigated for the presence of[unreadable] phosphorylation. Both the high-resolution capabilities of the exisiting FTICR and the sensitivity and flexibility[unreadable] of the Q-TOF, in combination with well established sample preparation methods such as IMAC, will allow for[unreadable] the unambiguous determination of protein constituents and associated post-translational modifications.